Increased Time to Surgery After Anterior Cruciate Ligament Tear in Female Patients Results in Greater Risk of Medial Meniscus Tear: A Study of 489 Female Patients

Timing of Anterior Cruciate Ligament Surgery

This narrative review examines the current literature for the influence of the surgical timing in the setting of anterior cruciate ligament (ACL) reconstruction on various outcomes. Although the exact definition of early and delayed ACL reconstruction (ACLR) is a subject of controversy, surgical timing influences arthrofibrosis and postoperative stiffness, quadriceps strength, postoperative knee function, and the incidence of intra-articular injuries to the menisci and cartilage. Additionally, there is a shortage of evidence regarding the role of ACLR timing in the setting of multiligament knee injury and when concurrent procedures are performed during the operative treatment of the ACL-injured knee.

Acute anterior cruciate ligament rupture: can repair become an alternative to reconstruction: a meta-analysis of randomized controlled trials and cohort studies

PURPOSE

To perform a meta-analysis to compare clinical outcomes of anterior cruciate ligament (ACL) repair and ACL reconstruction for acute ACL rupture.

METHOD

We searched Pubmed, Embase, the Cochrane Library, and Web of Science databases to seek relevant studies. Clinical outcomes included failure rate, hardware removal rate, anteroposterior (AP) knee laxity, and patient-reported outcomes. In addition, subgroup analysis was carried out according to repair techniques, rupture locations, and study designs. Funnel plots were used to detect publication bias. All statistical analysis was performed using STATA (version 14.2, StataCorp).

RESULTS

A total of 10 articles were included in this study, comprising 5 randomized controlled trials (RCTs) and 5 cohort studies, involving a total of 549 patients. We found no statistical differences between the ACL repair and ACL reconstruction in the following outcomes: failure rate, AP knee laxity, International Knee Documentation Committee (IKDC) score, Lysholm score, Knee Injury and Osteoarthritis Outcome (KOOS) Score, and Tegner score. However, the ACL repair group had a higher hardware removal rate. Except for AP knee laxity results on different repair techniques, there was no statistical difference in other subgroup analyses.

CONCLUSION

Compared with ACL reconstruction, ACL repair shows similar results in clinical outcomes, and it is promising to be an effective alternative treatment for acute ACL rupture. Larger samples and higher-quality studies are needed to support our results and further explore the advantages of ACL repair in other aspects.

LEVEL OF EVIDENCE

Level III.

Reduced physiological extrusion of the medial meniscus in axial load-bearing condition in anterior cruciate ligament deficiency

PURPOSE

In this study, ultrasonography was used to measure medial meniscus (MM) extrusion under weight-bearing and nonweight-bearing conditions in both anterior cruciate ligament (ACL)-deficient and ACL-intact knee groups. This study aimed to determine the possible differences between these groups with an eventual impact on meniscal tears in ACL-deficient knees.

METHODS

A total of 107 patients who underwent ACL reconstructive surgery between June 2022 and April 2023 were enroled. After applying exclusion criteria, 37 patients met the conditions for inclusion in the study and formed the ACL deficiency group (Group D). Of the 141 patients presenting to an outpatient clinic who agreed to have ultrasonography conducted on their nondiscomforting contralateral knee, 37 patients matched for age, sex, hip-knee-ankle angle and body mass index with Group D patients were selected for the ACL intact group (Group I). Ultrasonography was used to measure MM extrusion in weight-bearing and nonweight-bearing conditions for all participants.

RESULTS

Seventy-four patients were included in the study (n = 37 per group). The supine position showed an MM extrusion of 1.2 ± 0.7 mm in Group I and 1.2 ± 0.7 mm in Group D (not significant). In the standing position, MM extrusion measured 2.0 ± 0.6 mm in Group I and 1.3 ± 0.8 mm in Group D. The difference in extrusion (Δextrusion) between the two positions was 0.8 ± 0.6 in Group I and 0.1 ± 0.2 in Group D, with statistical significance (p < 0.01). A consistent reduction in MM extrusion during weight-bearing was observed in patients with ACL deficiency, irrespective of the duration of ACL deficiency, age, sex and BMI.

CONCLUSION

ACL deficiency did not significantly impact MM extrusion during nonweight-bearing conditions; however, less MM extrusion was observed in response to axial loading conditions. These findings indicate altered MM biomechanics due to increased anterior-posterior meniscal motion and rotational instability after ACL injury.

LEVEL OF EVIDENCE

Level III.

Robot-assisted anterior cruciate ligament reconstruction based on three-dimensional images

Background Tunnel placement is a key step in anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to evaluate the accuracy of bone tunnel drilling in arthroscopic ACL reconstruction assisted by a three-dimensional (3D) image-based robot system. Methods Robot-assisted ACL reconstruction was performed on twelve freshly frozen knee specimens. During the operation, three-dimensional images were used for ACL bone tunnel planning, and the robotic arm was used for navigation and drilling. Twelve patients who underwent traditional arthroscopic ACL reconstruction were included. 3D computed tomography was used to measure the actual position of the ACL bone tunnel and to evaluate the accuracy of the robotic and traditional ACL bone tunnel. Results On the femoral side, the positions of robotic and traditional surgery tunnels were 29.3 ± 1.4% and 32.1 ± 3.9% in the deep-to-shallow direction of the lateral femoral condyle (p = 0.032), and 34.6 ± 1.2% and 21.2 ± 9.4% in the high-to-low direction (p < 0.001), respectively. On the tibial side, the positions of the robotic and traditional surgical tunnels were located at 48.4 ± 0.9% and 45.8 ± 2.8% of the medial-to-lateral diameter of the tibial plateau (p = 0.008), 38.1 ± 0.8% and 34.6 ± 6.0% of the anterior-to-posterior diameter (p = 0.071), respectively. Conclusions In this study, ACL reconstruction was completed with the assistance of a robot arm and 3D images, and the robot was able to drill the bone tunnel more accurately than the traditional arthroscopic ACL reconstruction.

Causal relationship between obesity and meniscal injuries: Two-sample Mendelian randomization

To investigate the causal relationship between obesity and meniscal injuries using Mendelian randomization (MR). Genetic loci independently associated with obesity and meniscal injuries in people of European origin were selected as instrumental variables using pooled data from genome-wide association studies. Three MR analyses, MR-Egger, weighted median and inverse variance weighting, were used to investigate the causal relationship between obesity and meniscal injuries. The results were tested for robustness by heterogeneity and multiplicity tests, and sensitivity analyses were performed using the "leave-one-out" method. The inverse variance weighting results showed an OR (95% CI) of 1.13 (1.04-1.22), P = .003, indicating a causal relationship between obesity and the occurrence of meniscal injuries. And no heterogeneity and multiplicity were found by the test and sensitivity analysis also showed robust results. In this study, genetic data were analyzed and explored using 2-sample MR analysis, and the results showed that obesity is a risk factor for meniscal injuries.

Delaying ACL reconstruction is associated with increased rates of medial meniscal tear

PURPOSE

The aim of this study was to evaluate the relationship between the time from injury to ACL reconstruction (ACLR) and the rate as well as repairability of meniscal tears. Secondary aims were to evaluate the relationship between meniscal injury and Tegner Activity Scale, age, BMI, and gender.

METHODS

Between 2012 and 2022, 1,840 consecutive ACLRs were performed. A total of 1,317 ACLRs were included with a mean patient age of 31.2 years ± 10.5 [16-60]. Meniscal tear was assessed during arthroscopy using the ISAKOS classification. Time from injury to ACLR, Tegner Activity Scale, age, BMI and gender were analysed in uni- and then in multivariate analyses. Patients were divided into four groups according to the time from injury to surgery: < 3 months (427; 32%), 3-6 months (388; 29%), 6-12 months (248; 19%) and > 12 months (254; 19%).

RESULTS

Delaying ACLR > 12 months significantly increased the rate of medial meniscal (MM) injury (OR 1.14; p < 0.001). No correlation was found between a 3- or 6-month time from injury to surgery and MM tear. Performing ACLR > 3, 6, or 12 months after injury did not significantly increase the rate of lateral meniscal (LM) injury. Increasing Tegner activity scale was significantly associated with a lower rate of MM injury (OR 0.90; p = 0.020). An age > 30 years (OR 1.07; p = 0.025) and male gender (OR 1.13; p < 0.0001) was also associated with an increased rate of MM injury. Age > 30 years decreased the rate of MM repair (OR 0.85; p < 0.001). Male gender increased the rate of LM tear (OR 1.10; p = 0.001).

CONCLUSION

Performing ACLR more than 12 months after injury was associated with increased rates of MM injury but not with lower rates of repairable lesions. An increased pre-injury Tegner activity score was associated with a decreased rate of MM tear. Age > 30 years was associated with an increased rate of MM tear with concomitant ACL injury and a decreased rate of repairability of MM tear. ACLR should be performed within 12 months from injury to prevent from the risk of MM injury.

LEVEL OF EVIDENCE

Level III.

Delayed ACL reconstruction increases rates of concomitant procedures and risk of subsequent surgery

PURPOSE

To utilise a large cross-sectional database to analyse the effects of time duration between diagnosis of anterior cruciate ligament (ACL) tear and ACL reconstruction (ACLR) on concomitant procedures performed and subsequent surgery within 2 years.

METHODS

An analysis from 2015 to 2018 was performed using the Mariner PearlDiver Patient Records Database. Current Procedural Terminology (CPT), and International Classification of Diseases (ICD-10) codes identified patients with a diagnosis of ACL tear who underwent subsequent ACLR. Patients were stratified in biweekly and bimonthly increments based on the time duration between initial diagnosis of ACL tear and surgical treatment. Chi-squared analysis was used to compare categorical variables, and trend analysis was performed with Cochran-Armitage independence testing.

RESULTS

Of 11,867 patients who underwent ACLR, 76.1% underwent surgery within 2 months of injury diagnosis. Patients aged 10-19 were most likely to undergo surgery within 2 months of injury diagnosis (83.5%, P < 0.0001). As duration from injury diagnosis to ACLR increased from < 2 months to > 6 months, rates of concomitant meniscectomy increased from 9.1% to 20.5% (P < 0.0001). The overall 2-year subsequent surgery rate was 5.3%. The incidence of revision ACLR was highest for patients who underwent surgery > 6 months after diagnosis (P < 0.0001), whilst the incidence of ipsilateral lysis of adhesions and manipulation under anaesthesia (MUA) was highest for patients who underwent surgery < 2 months after diagnosis (P < 0.0001). ACLR at 6-8 weeks after diagnosis demonstrated the lowest risk for concomitant procedures as well as 2-year subsequent surgery.

CONCLUSION

The majority of patients undergo ACL reconstruction within 2 months of initial ACL tear diagnosis. Delayed surgery greater than 6 months after the diagnosis of an ACL rupture leads to increased need for concomitant meniscectomy as well as higher risk for revision ACLR within 2 years, but immediate surgery may increase risk for knee arthrofibrosis.

LEVEL OF EVIDENCE

IV.